Vehicle Diagnostic, Testing and
Information System VAS 5051
Design and Functions
Self study program No. 202
The Vehicle Diagnostic, Testing and Information System VAS 5051 ...
202/001
... for state-of-the-art fault finding!
This innovative system provides mechanics with comprehensive support in
concentrated form for finding faults in the electronic systems of vehicles.
The mechanic can be supported by the guided fault finding mode, or also carry
out his own variable test sequences using the test instruments and self-diagnosis.
The system provides help for operation and fault detection.
2
List of contents
Main components of the VAS 5051
Why another new diagnostic system? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Fundamentals of system. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Design and features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Summary of tester. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Modes
Start screen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Administration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Vehicle self-diagnosis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Test instruments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Guided fault finding. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
12
13
14
16
18
Measurements and analysis with the VAS 5051
Multimeter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Digital Storage Oscilloscope (DSO) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Sensor analysis with the DSO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Actuator analysis with the DSO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Before switching on the diagnostic system, refer to the supplied Instruction Manual for information on how to use it and on special features.
The private study program
is not a workshop manual!
New!
Caution!
Note!
For test, adjustment and repair
instructions, please refer to the
provided servicing literature.
3
Main components of the VAS 5051
Why another new diagnostic
system?
Modern electronics makes our cars increasingly
safe, comfortable and environment-friendly.
The associated increased networking of the electronic vehicle systems makes fault finding
increasingly complex and time-intensive.
Since the previous vehicle system testers only
indicate the path in which the fault is to be found,
fault finding is sometimes delayed by lengthy
measurements and studying of various workshop
manuals.
The frequently used suspicion-based repairs
result in unnecessary burdens on the customers
and the mechanics as a result of multiple repairs.
The VAS 5051 vehicle diagnostic, testing and
information system is now putting an end to this
situation.
The new system combines the vehicle self-diagnosis, test instruments and technical
documentation with state-of-the-art technology.
Use of the VAS 5051 enables fault finding on the
vehicle to be carried out more rationally, precisely, clearly and economically:
- Because you receive exact instructions on
what you have to do and where in all
phases of the "Guided Fault Finding" on
the touchscreen;
operating faults are practically eliminated.
- Because the fault memories of the control
units are read via the diagnostic interface
to the vehicle, and an objective test plan is
automatically derived from this.
- Because you can select hierarchically listed
data from selection lists for vehicle identification, input of fault characteristics or
selection of functions, groups of components and individual components.
- Because you can display associated documentation for selected functions, groups of
components or individual components, and
print this if required.
Because of its state-of-the-art technology and
future-oriented capabilities, all workshops of the
group worldwide will be equipped with the new
VAS 5051.
The VAS 5051 can be used for all marques
of the Volkswagen Group.
4
Fundamentals of system
The VAS 5051 is a knowledge-based system.
The knowledge base is present on a CD-ROM
and includes the latest knowledge on:
- Equipment
- Fault codes of control units
- Fault characteristics
- Vehicle design with respect to functions
and components
- Function tests
- Technical documentation.
The data are combined in hierarchical architectures and linked to one another.
The knowledge base is generated using a diagnostic development system.
It can be easily supplemented and modified, thus
permitting adaptation to new vehicles.
The incorporation of new documents is also possible, as is the utilization of workshop experience
with e. g. new fault characteristics and their
assignments.
As a result of the knowledge base, the diagnostic
system is able:
- To identify a vehicle and its standard/
optional equipment
- To carry out an automatic system test of the
electronic systems fitted in the vehicle
- To carry out a "Guided fault finding"
according to a test plan by selecting fault
characteristics
- To use own knowledge by direct selection of
tests
- To generate easy-to-use self-diagnosis functions
- To generate new test plans following automatic incorporation of a function test.
5
Main components of the VAS 5051
Design and features
Measuring leads
Tester
Workshop trolley
Printer
202/002
VAS 5051 system features:
- Portable equipment powered via a mains
connection or the diagnostic interface in the
vehicle, an integrated battery provides a
brief backup supply
- Infrared interface for control of printer
- Operation using pressure-sensitive colour
touchscreen
- Prepared for remote diagnosis via retrofit
ISDN connection
- Integrated diagnostic and test instrument
module
- Integrated CD-ROM drive for CD-ROM with
repair information in required language
6
- VGA interface (video graphics adapter) for
connection of an external monitor
Summary of tester
202/004
The functional centrepoint of the VAS 5051 is the
tester with its LCD touchscreen.
The tester is a combination of measuring instrument and computer.
When mounted on the workshop trolley, the complete system is mobile, and all equipment
required for diagnosis is permanently within
reach.
The tester can also be transported individually
using the handle, e. g. into the vehicle interior.
The operating system and applications program
are stored internally.
The vehicle-specific data, test programs and
other technical documents are read in from
replaceable CD-ROMs using the built-in CDROM drive, and saved on the hard disk in the
tester.
Updates are possible by simply using a new CD.
The tester is controlled by touching corresponding text positions or navigation elements on the
screen.
A laser printer is activated via an infrared interface without additional cabling.
This prints documents, and also hardcopies of
the screen as required.
7
Main components of the VAS 5051
Front
VAS 5051
Vehicle Diagnostic, Testing and Information System
Version -GB- / V02.00 22/10/97
Vehicle
Self-Diagnosis
Test
Instruments
Guided
Fault Finding
Administration
Help
VAS 5051
202/003
The front of the tester is the screen which is used
for information purposes and for communication
with the mechanic.
The graphic displays on the screen are referred
to as "masks". They display all information and
functions of the tester.
The tester is operated using the touchscreen
which covers the complete surface.
This detects the pressure applied via your finger
or other objects, and thus replaces a mouse and
keyboard.
A text or navigation element provided for controlling the tester can be recognized by a change
in colour.
The selected control element is only activated
when the pressure produced by touching is
removed.
Do not use any pointed or hot objects
to operate the screen, or any objects
which leave colours behind.
Such objects damage the screen.
8
The tester switches to power saving
mode if it is not used for several
minutes.
When the screen is touched, the mask
that was last accessed is displayed
again.
Left side
The connections are located behind a cover panel.
Only the connection for the mains cable is required
for workshop operation.
The other connections are required for servicing or
repairs and for later extension of the tester's scope
of functions.
SIEMENS
VGA interface
An external monitor can be connected to the VGA
interface.
Serial interface
Keyboard interface
The serial interface and the keyboard interface are
only provided for servicing work on the tester.
The PC card interface is used for subsequent extension of the tester, e. g. remote diagnosis.
PC card interface
Connection for the
mains cable
202/005
No other interfaces may be used
apart from the mains connection and
the VGA interface.
Faults resulting from the use of other
interfaces lead to cancellation of the
guarantee.
Right side
The CD-ROM drive is required to update the diagnostic system.
The tester loads the new program version from the
CD-ROM onto the hard disk.
Diskette drive
CD-ROM drive
Be careful not to overwrite a
newer program version, otherwise
important data and functions
could be lost.
Infrared interface
ON/OFF switch
The diskette drive is not required for workshop
operation.
The infrared interface permits data transmission to
the printer without wiring.
202/006
9
Main components of the VAS 5051
Top
DSO measuring lead 2
VAS 5051/8
DSO measuring lead 1
VAS 5051/8
DSO 1
DSO 2
TZ
KV
SZ
T/D
Trigger pick-up, option
VAS 5051/18
Current pick-up 50A
VAS 5051/9
Current pick-up 500 A, option
VAS 5051/19
kV sensor, option
VAS 5051/17
Control unit
Diagnostic socket,
16-contact
10
Prepared signal inputs for pressure and temperature
U/R/D measuring lead with button for voltage and resistance measurements, diode and continuity tests as well
as...
Handle
... for inline current measurements
VAS 5051/7
U/R/D
DIAG
10 A
COM
COM measuring lead with safety test probe
VAS 5051/7
Fuse for inline current
measurements
Diagnostic adapter
VAS 5051/2
Diagnostic cable 3 m
VAS 5051/1
202/008
All measuring leads and connections on
the tester are colour-coded.
Make sure the colours match when
connecting.
11
Modes
Start screen
VAS 5051
Vehicle Diagnostic, Testing and Information System
Version -GB- / V02.00 22/10/97
Vehicle
Self-Diagnosis
Test
Instruments
Guided
Fault Finding
Administration
Help
202/047
The operating program is started automatically
when you switch on the tester.
The tester is ready for use when the system start
mask is displayed on the screen.
When switching on the tester for the first time,
the mode buttons "Vehicle Self-Diagnosis", "Test
Instruments" and "Guided Fault Finding" are not
yet visible.
The complete system start mask appears when
you enter the dealership identifier in the mode
"Administration".
12
You can start the following modes from the system start mask:
- Vehicle self-diagnosis
- Test instruments
- Guided fault finding
- Administration.
The "Help" function can be selected in all modes
and provides information on operation and on
the functions of the individual navigation
buttons.
Administration
Equipment number: 12345
Importer number: 678
Dealership number: 98765
John Smith, Ltd.
Administration
Administration
Select
function
Install update
Self-test
Change dealership identifier
Signal generator
Date/time
Expanded functions
Change language
Select initial graphic
CD contents list
Go to
Help
202/025
The diagnostic system can be adjusted in mode
"Administration".
The function "Install update" lets you download a
newer program version from the CD-ROM onto
the hard disk.
The language-specific setting of the system is
carried out simultaneously from this CD-ROM.
The function "Self-test" permits internal checking
of the test instrument unit and diagnostic unit of
the tester.
Further settings (such as date, time and signal
pitch) can be individually adjusted according to
requirements.
By selecting the initial graphic, it is possible to
modify the marque-specific default setting of the
vehicle display and the logo in the system start
mask.
The expanded functions are not required for use
in the workshop.
The workshop code (VZ or importer number and
dealership number) is entered once following
starting-up of the tester.
It is subsequently only possible to change the
dealership identifier (dealer's address).
13
Modes
Vehicle self-diagnosis
VAS 5051
Vehicle Diagnostic, Testing and Information System
Version -GB- / V02.00 22/10/97
Vehicle
Self-Diagnosis
The mode "Vehicle Self-Diagnosis" is activated
by selecting the navigation element with this
name in the system start mask.
Test
Instruments
Guided
Fault Finding
Administration
Help
202/049
The mode "Vehicle Self-Diagnosis" provides the
functions of the currently available V.A.G. 1551
and V.A.G. 1552 diagnostic testers.
Communication is carried out as usual via the
diagnostic interface of the vehicle.
The vehicle self-diagnosis program helps the
mechanic by guiding him through a dialog.
14
In addition, the tester is being developed further
in order to be able to carry out the programming
of control units (flash programming) in this mode
in the future.
A requirement for use of the self-diagnosis mode
is that the current workshop manual is available
for the respective vehicle.
Vehicle Self-Diagnosis
Select vehicle system
01 - Engine electronics
41 - Diesel pumpe lektronics
Engine electronics
Self-Diagnosis
02 - Gearbox Vehicle
electronicsG
028906021CK 1.9l R4 EDC
12 - Clutch electronics
G00SG 0802
03 - Brake system
Selectelectronics
diagnostic
Coding 2
14 - Suspension
electronics
function
Workshop code 79415
24 - Traction control system
34 - Self-levelling
suspension
02 Interrogate fault memories
Vehicle Self-Diagnosis
15 - Airbag 03 Final control diagnosisiInterrogate fault memory
25 - Immobilizer
04 Basic setting
35 - Central locking
0
05 Erase fault memory 1 fault(s) detected
45 - Interior monitoring
Endcontrol
output
55 - Headlight06range
522
Code
control unit
16 - Steering 07
wheel
electronics
Coolant temperature sender - G62
08 Read
data block
26 - Electronische
DachbetŠtigung
Open/short circuit to positive
36 - Seat adjust
10 Adaption
46 - Convenience
system
central module
sporadically
11 Login
procedure
56 - Radio
66 - Seat/mirror adjustment
76 - Parking aid
17 - Dash panel insert
Sprung
08 - AC/heater electronics
Druck
Hilfe
Test
Instruments
18 - Additional/auxiliary heater
Interrogate all fault memories
Select vehicle system via address word
OBDII
Test
Instruments
Go to
Drucken
Test
Instruments
Go to
Engine electronics
028906021CK 1.9l R4 EDC
G00SG 0802
Coding 2
Workshop code 79415
Print
Help
Hilfe
202/021
The vehicle systems or functions can be selected
using the highlight bars.
When "Interrogate all fault memories" is
selected, all control units present in the vehicle
are interrogated and displayed.
In the screen mask "Select diagnostic function"
you can select the various functions which are to
be carried out with the selected control unit.
With "Interrogate fault memory", a list of faults is
displayed in the next screen mask.
The control unit identification is displayed
following establishment of communication.
15
Modes
Test instruments - Multimeter
VAS 5051
Vehicle Diagnostic, Testing and Information System
Version -GB- / V02.00 22/10/97
The mode "Test Instruments" is activated by
selecting the navigation element with this name
in the system start mask.
Vehicle
Self-Diagnosis
Test
Instruments
Guided
Fault Finding
Administration
Help
202/048
Test Instruments
Multimeter
Voltage (U/R/D)
Freeze Frame
11.43 V
Minimum
Maximum
-20.00
0
Voltage
(U/R/D)
Resistance
(U/R/D)
Inline
current
Continuity test
(U/R/D)
Diode test
(U/R/D)
20.00
Current 50 A
curr. pick-up
Current 500 A
curr. pick-up
Voltage
DSO 1
± 20 V
Calibrate
DSO
Go to
Print
Help
202/022
In mode "Test Instruments" it is possible to work
with the "Multimeter" or the "Digital storage
oscilloscope".
The multimeter can be used to measure all electrical variables present in the vehicle such as DC
and AC voltages/currents and resistances.
The test instruments deliver data with a high
accuracy.
Currents can be measured inline, i.e. by connection into the cable, or by using the current pickup.
Continuity and diode tests can also be carried
out.
16
Digital storage oscilloscope
Test Instruments
Multimeter
Voltage (U/R/D)
Freeze frame
0.001 V
Minimum
Maximum
-2.000
0
Voltage
(U/R/D)
Resistance
(U/R/D)
Inline
current
Continuity test
(U/R/D)
Diode test
(U/R/D)
2.000
Current 50 A
curr. pick-up
Current 500 A
curr. pick-up
Voltage
DSO 1
± 2V
Calibrate
The measuring mode "Digital storage oscilloscope" is activated by selecting the navigation
element with this name in the "Test Instruments"
screen.
DSO
Go to
Print
Help
202/050
Test Instruments
DSO
2 V/Div.=
Auto mode
10 ms/Div.
Freeze Frame
Channel A
Channel B
Trigger mode
0
T
Time/Div.
Multimeter
Position
Go to
Measuring
mode
Print
Help
202/082
Return to multimeter
The digital storage oscilloscope (DSO) stores the
current values of an analog signal using an
adjustable time base.
The stored values are displayed as a curve on the
screen.
The DSO can be used to display the voltage
waveshapes of two channels simultaneously.
The required measuring leads are included in the
equipment package.
17
Modes
Guided fault finding
VAS 5051
Vehicle Diagnostic, Testing and Information System
Version -GB- / V02.00 22/10/97
Vehicle
Self-Diagnosis
Test
Instruments
Guided
Fault Finding
The mode "Guided Fault Finding" is activated
by selecting the navigation element with this
name in the system start mask.
Administration
Help
202/019
Guided fault finding is the actual innovation with
which the VAS 5051 facilitates workshop operations and shortens the time required to find
faults.
Starting from fault signals from the vehicle selfdiagnosis, a brief description of the customer
complaints, or assumptions concerning the cause
of the fault, the mechanic is guided step-by-step
through a fault finding program.
This fault finding program is permanently generated and optimized in the computer during the
test.
18
The test instrument and self-diagnosis functions
are implemented as necessary during guided
fault finding.
All information from various workshop documents required for fault finding, e. g.:
- Workshop manuals
- Fault finding programs
are included in the programs of the mode
"Guided fault finding".
Guided Fault Finding
Vehicle identification
Type
VW
AUDI
SEAT
SKODA
Guided Fault Finding
Vehicle identification
Select type
VW
VW
Passat 1994>
1996
Estate
Guided Fault Finding
Vehicle identification
Polo 1995>
Select
Golf 1992>, Version
engine code
VW
Passat 1988>
Guided Fault Finding
Passat 1994>
Passat 1994>
1Z 1.9l Turbodiesel Vehicle identification
1996
Caddy 1996>
AAA 2.8l Motronic VRConfirm
Estate
Sharan 1996>
AAM 1.8l Monomotrovehicle identification
AFN 1.9l Turbodiesel engine/ 81 kW
Caddy Pickup 1 AAZ 1.9l Turbodiesel
If vehicle has been correctly identified, choose "C
VW
Taro
Guided
Fault
Finding
ABF 2.0l Digifant/ 11
Passat 1994>
Transporter 1996 ABV 2.9l Motronic/ 1 continue (>)" to confirm.
Vehicle identification
1996
LT
Sprung2.0l Simos/
Druck
Me§technik
ADY
85 Hilfe
Connect VAS 5051
Estate
ADZ 1.8l Monomotro Choose "Back" and
to vehicle
AFN 1.9l Turbodiesel engine / 81 kW
AEK 1.6l Motronic step-by-step.
With the ignition switched off connect the VAS 5051
AFN 1.9l Turbodiesel
Sprung
Druck
Hilfe
Test
to the diagnostic connector as follows:
Instruments
Choose "Go to
AFT 1.6l Simos/ 74 kW
- Removing cover for diagnostic connection on
to enter the seö
AGG 2.0l Simos/ 85 kW
right.
VW
Guided Fault Finding
Sprung
Druck
Hilfe
Test
Instruments
Passat 1994>
Vehicle system test
Choose "Go to"prung
VAS 5051
Fahrzeugdiagnose-, Me§-und Informationsystem
Version -D-/0.1, 18.04.96
POLO
VAS 5051
1996
Estate
AFN 1.9l Turbodiesel engine / 81 kW
to return to thel
Airbag
Test
Instruments
Sprung
Druck
Hilfe
Diesel direct injection and preheating system
Fault
VAS 5051/1
Automatic gearbox 01M
N01-0103
ABS / EDS Teves 20 GI
Test
Instruments
Sprung
ABS Teves 20 GI
Druck
Hilfe
Airbag
Climatronic
Immobilizer
Help
202/020
When starting the fault finding procedure, the
vehicle must first be identified by a systematic
interrogation algorithm.
This guarantees unambiguous assignment of all
documents and test values for the subsequent
fault finding procedure.
The vehicle system test is started automatically.
When interrogating the individual control units,
all faults found are displayed in succession.
Faults can be selected individually and eliminated step-by-step according to the program
specifications.
19
Modes
Guided Fault Finding
Complaint report
VOLKSWAGEN
Passat 1997 >
1997
Saloon
ADR 1.8l Motronic / 92 kW
Select
complaint
Complaint directly related to repair group
Complaint related to observation
Guided Fault Finding
Complaint report
Select
subsystem / observation
Start
Lamps and lights
Braking process
Acceleration
Meßtechnik
Guided Fault Finding
Complaint
report Drucken
Sprung
FahrzeugEigendiagnose
Lamps and lights
Hilfe
Select
type / component
ABS warning lamp -K47- does not go out
Braking system warning lamp -K118- does not go out
Warning lamp for ABS and for brake system do not go out
Reversing lamps do not light up
Meßtechnik
FahrzeugEigendiagnose
Sprung
Drucken
Guided Fault Finding
Complaint report
Hilfe
Lamps and lights
ABS warning lamp -K47- does not go out
Display all selections
Lamps and lights ABS warning lamp -K47- does not go out
VOLKSWAGEN
Passat 1997 >
1997
Saloon
ADR 1.8l Motronic / 92 kW
Guided Fault Finding
Complaint report
Meßtechnik
FahrzeugEigendiagnose
Sprung
Drucken
Display all selections
Hilfe
ABS warning lamp -K47- does not go out
Power supply
N55 - hydraulics control unit for ABS
K47 - warning lamp for ABS
Meßtechnik
FahrzeugEigendiagnose
Test
Instruments
Sprung
Vehicle
Self-Diagnosis
If no faults have been detected during the vehicle system test, it is possible to select complaints
according to observed fault characteristics when
using the mode "Guided fault finding".
Following input of the complaint, a special test
plan is generated by the tester for the displayed
fault characteristics.
The tester guides the mechanic through the test
plan using a dialog.
20
Drucken
Go to
Hilfe
Print
Help
202/052
All test conditions and steps necessary up to
elimination of the fault as well as the test equipment and activities required for the individual
tests are defined.
VOLKSWAGEN
Passat 1997 >
1997
Saloon
ADR 1.8l Motronic / 92 kW
Guided Fault Finding
Function test
Supply voltage to ABS
control unit
Test conditions
V.A.G 1598
Yes
Test conditions
No
- Fuse S20 OK
Are the conditions fulfilled?
Guided Fault Finding
Function test
VOLKSWAGEN
Passat 1997 >
1997
Saloon
ADR 1.8l Motronic / 92 kW
Supply voltage to ABS
control unit
V.A.G 1598/27
N01-0116
Check power supply
Test Instrument
Vehicle self-diagnosis
Go to
Druck
Help
Done
Eigendiagnose
The power supply
will now be checked
Measunging
equipment
- Switch off the ignition.
- Disconnect the plug of the ABS
control unit -J104-. The control
unit is located on the hydraulics
unit on the left in the engine compartment.
- Connect the V.A.G. 1598 test box to the
wiring harness using the V.A.G. 1598/27
adapter.
- Switch on the ignition.
Test
Instruments
Vehicle
Self-Diagnosis
Supply voltage to ABS
control unit
Testbox V.A.G 1598/27: Measuring equipment
Print
Go to
Help
V.A.G 1598
VOLKSWAGEN
Passat 1997 >
1997
Saloon
ADR 1.8l Motronic / 92 kW
Guided Fault Finding
Function test
Supply voltage to ABS
control unit
VOLKSWAGEN
Passat 1997 >
1997
Saloon
ADR 1,8l Motronic / 92 kW
Guided Fault Finding
Function test
Print function
Screen
V.A.G 1598/27
DiagnosisN01-0116
log
Document
Check power supply
Done
URD cable (+) to test box socket 15
COM cable (-) to test box socket 19
Check power supply!
Guided Fault Finding
Function test
Test
Instruments
Check power supply
Voltage
measurement
Vehicle self-diagnosis
Go to
Go to
Print
Help
VOLKSWAGEN
Passat 1997 >
1997
Saloon
ADR 1.8l Motronic / 92 kW
Supply voltage to ABS
control unit
Test
Instruments
Vehicle
Self-Diagnosis
Druck
Eigendiagnose
Supply voltage to ABS
control unit
URD cable (+) to test box socket 15
COM cable (-) to test box socket 19
Check power supply!
Target value OK: 10 ... 15 V
10.00
- 20.00
VOLKSWAGEN
Passat 1997 >
1997
Saloon
ADR 1.8l Motronic / 92 kW
Guided Fault Finding
Fertig
Function test
Help
Check power supply
15.00
20.00
There is no voltage on the control unit.
Electrical measurements will now be made
on the wiring.
- Switch off the ignition!
Done
0.00 V
Test
Instruments
Vehicle
Self-Diagnosis
Go to
Print
Help
Test
Instruments
Vehicle
Self-Diagnosis
Go to
Print
Help
202/053
Following termination of the fault finding, you
can print a report of the test steps using the function "Print/diagnosis log".
21
Measurements and analysis with the VAS 5051
Multimeter
Display of measuring function
Test Instruments
Multimeter
Display active connection
U – voltage
R – resistance
D – continuity/diode
Freeze frame function, activation
also possible using button on
measuring lead
Voltage (U/R/D)
Freeze Frame
11.43 V
Minimum
Maximum
-20.00
0
Voltage
(U/R/D)
Resistance
(U/R/D)
Inline
current
Continuity test
(U/R/D)
Diode test
(U/R/D)
20.00
Current 50 A
curr. pick-up
Current 500 A
curr. pick-up
Voltage
DSO 1
± 20 V
Calibrate
DSO
Go to
Print
Display of minimum and maximum values during measurement
Buttons for selection
of measuring function
Help
202/022
Button for selection of measuring mode
- DC voltage
- AC voltage
Buttons for selection of measuring range setting
The display field for the measuring range is not selected in the above display, i.e.
autoranging is activated in this case.
The selectable measuring functions in the mask
"Multimeter" are divided into two function blocks:
•Function block 1
(measurements using U/R/D measuring lead)
- Inline current
- Voltage
- Resistance
- Diode test
- Continuity test
•Function block 2
(measurements using current pick-up, DSO 1)
- Current
50 A, current pick-up
- Current 500 A, current pick-up
- Voltage, DSO 1
Use of the test instruments is possible without
previous identification of the vehicle.
22
Test Instruments
Multimeter
Inline current
To carry out a current measurement (inline),
the U/R/D measuring lead must be plugged
into the 10-A signal input on the tester.
Freeze Frame
0.470 A
Minimum
Maximum
-1.000
1.000
0
Voltage
(U/R/D)
Resistance
(U/R/D)
Inline
current
Continuity test
(U/R/D)
Diode test
(U/R/D)
Strom 50 A
Stromzange
Strom 500 A
Stromzange
Voltage
DSO 1
Go to
Print
Help
Calibrate
1A
DSO
202/070
Test Instruments
Multimeter
Voltage (U/R/D)
To carry out a voltage, resistance, diode test or
continuity test measurement, the U/R/D measuring lead must be plugged into the U/R/D signal
input on the tester.
Freeze Frame
11.43 V
Test Instruments
Multimeter
Resistance (U/R/D)
Minimum
Maximum
-20.00
0
Voltage
(U/R/D)
Resistance
(U/R/D)
Inline
current
Continuity test
(U/R/D)
20.00
2.51 MΩ
Inline 50 A
Inlinezange
Diode test
(U/R/D)
Inline 500 A
Inlinezange
Freeze Frame
Voltage
DSO 1
Kalibrieren
Test Instruments
Multimeter
Continuity test (U/R/D)
Minimum
Maximum
0.00
± 20 Voltage
V
(U/R/D)
Inline
current
10.00
Resistance
(U/R/D)
Continuity test
(U/R/D)
Diode test
(U/R/D)
Inline 50 A
Inlinezange
Sprung
Drucken
Inline 500 A
Inlinezange
Freeze Frame
Kalibrieren
Voltage
DSO
DSO
1
Test Help
Instruments
Multimeter
Diode test (U/R/D)
Freeze Frame
0 .. 10 MOhm
Voltage
(U/R/D)
Resistance
(U/R/D)
Inline
current
Continuity test
Sprung
(U/R/D)
0 .. 10 Ohm
Inline 50 A
Inlinezange
Diode test
(U/R/D)
Inline 500 A
Inlinezange
DSO
+
Drucken
Kalibrieren
Voltage
DSO 1
–
Help
Voltage
(U/R/D)
Resistance
(U/R/D)
Inline
current
Sprung test
Continuity
(U/R/D)
Diode test
(U/R/D)
Drucken
Current 50 A
curr. pick-up
Current
DSO 500 A
curr. pick-up
Voltage
DSO 1
Print
Help
Calibrate
Help
20 V
DSO
Go to
202/071
23
Measurements and analysis with the VAS 5051
Test Instruments
Multimeter
Voltage U/R/D
Voltage DSO1
Freeze frame
12.7 V
Voltage
(U/R/D)
Resistance
(U/R/D)
Inline
current
Continuity test
(U/R/D)
14.9 V
Current 50 A
curr. pick-up
Diode test
(U/R/D)
20 V
Current 500 A
curr. pick-up
Voltage
DSO1
Print
Help
Calibrate
40 V
Go to
It is possible to simultaneously measure different
voltages via the connections U/R/D and DSO 1,
and to compare them on the display.
The U/R/D voltage and the buttons for selection
of the measuring range are located on the left.
Everything on the right applies analogously to
the DSO 1 connection.
DSO
202/054
Test Instruments
Multimeter
Current 50 A current pick-up
Freeze frame
0.239 A
Minimum
Maximum
-5.000
0
Voltage
(U/R/D)
Resistance
(U/R/D)
Inline
current
Continuity test
(U/R/D)
Diode test
(U/R/D)
5.000
Current 50 A
curr. pick-up
Current 500 A
curr. pick-up
Voltage
DSO 1
Print
Help
±5A
Go to
Calibrate
DSO
202/068
24
The current measurement is made using a current
pick-up (current pick-up 50 A included in equipment package). The current following through the
cable is measured when the pick-up is closed.
Measurements are possible on wires with a
diameter up to 20 mm.
Digital storage oscilloscope
Scanning frequency
Test Instruments
DSO
2 V/Div.=
The associated operating functions
become visible when a channel is
selected.
Auto mode
10 ms/Div.
Freeze Frame
Channel A
Channel B
Trigger mode
0
T
Measuring
mode
Adjustment of trigger signal
Selection of measuring mode
Time/Div.
Multimeter
Position
Go to
Help
Print
202/067
Adjustment of scanning frequency
Shifting of curve
The graphic waveshapes of the curves can be
displayed in the mask "DSO" and compared with
one another.
Parameters can be set, measurements triggered,
and the measured values of individual curves
read.
Scanning frequencies and amplitudes are set
using the various arrow buttons in the masks.
The signals present in channels A or B can be
selected using the buttons "Channel A" and
"Channel B" and set individually.
The trigger channel is selected and set using the
button "Trigger mode".
The objective of triggering is to establish a fixed
relationship between the measured voltage and
the sweep generated in the equipment. The result
can be stationary oscillograms for single signals
and for signals repeated at irregular intervals.
The trigger point is the point of the curve which
corresponds to the beginning of the measurement.
The signal response prior to the trigger point is
also displayed depending on the position of the
trigger point on the screen.
The measurements should preferably be made in
"Auto setup mode" of the measuring mode.
Recorded curves can be compared with a
defined curve for correctness using the function
"Preset measurement".
25
Measurements and analysis with the VAS 5051
Display of active measure mode
Scanning frequency
Measuring range
amplitude channel A
Test Instruments
DSO
Auto mode
5 V/Div.=
50 ms/Div.
Freeze Frame
Channel A
Channel B
Trigger mode
0
Measuring
mode
Measuring mode mask
is activated
5 V/Div.=
Auto Setup
Auto Level
Auto
Normal
Single
Go to
Print
Draw mode
Multimeter
Help
202/083
Measuring range
amplitude channel B
The button "Measuring mode" can be used to set
the following methods of data measurement:
- Auto setup
- Auto level
- Auto
- Normal
- Single
- Draw mode
If an unknown signal is present, the measure
mode "Auto setup" presents advantages.
In auto setup mode, the amplitudes of channels
A and B, the scanning frequency, and the trigger
threshold are set automatically.
A change is then made automatically to the
mode "Auto level", and the measurement continued independent of the signal amplitude.
Measuring is carried out automatically and freerunning if the measure mode "Auto" is selected.
The signal is displayed either following a valid
trigger event or following expiry of the wait time
determined by the scanning frequency.
26
Selection of types of measuring mode
A trigger event is present if the entered input signal has been triggered, i.e. a time and phase
reference has been produced.
A signal is only displayed on the screen in measuring mode "Normal" if a trigger signal is
present and the trigger level is correctly set to the
input signal.
A measurement is only carried out once in measuring mode "Single" following a valid trigger
event. A new single recording is carried out each
time the button is pressed.
The measure mode "Draw mode" should be set
for signals which only change slowly, e. g.
lambda probe or temperature sender. Recording
of the measured value is untriggered, the curve is
displayed continuously from left to right.
Trigger point
Auto level mode
Test Instruments
DSO
5 V/Div.=
20 ms/Div.
Freeze Frame
Channel A
Trigger mode mask
is activated
Channel B
Trigger mode
T
0
Measuring
mode
Slider for setting of trigger
level
5 V/Div.=
0.0
Channel
Coupling
Edge
Go to
Print
Multimeter
Help
202/084
Arrow buttons for shifting of trigger point
The button "Trigger mode" is used to activate the
input functions for setting the trigger signal.
The signal connection (e. g. DSO 1, DSO 2, pickup, kV) for the trigger signal can be selected by
pressing the button "Channel".
When pressing the button "Coupling", a selection menu appears depending on the selection of
channel A or B.
High-frequency or low-frequency filtering of the
trigger signal can be carried out in this menu.
The button "Edge" opens a further menu with the
possible selections "neg." or "pos.".
The falling edge of the trigger signal or input signal is used when selecting "neg.", the rising edge
when selecting "pos.".
The trigger level can be changed by moving the
slider.
Shift upwards to select positive voltage values,
and downwards to select negative values.
The buttons "Coupling" and "Edge" are omitted
if the signal connection "Pick-up" is selected.
When connecting the measuring leads
of the DSO, check that the polarity and
the respective connection points are
correct. The signal shape is largely
determined by the connection points.
Both signal cables should preferably be
connected to the sensor or actuator.
27
Measurements and analysis with the VAS 5051
5 V/Div.=
The operating functions for channel A are displayed by pressing the button "Channel A".
Auto level mode
Test Instruments
DSO
0,1 s/Div.
Freeze Frame
Channel A
Channel B
0
Trigger mode
0
The button "Channel" activates the signal connection (e. g. DSO 1, DSO 2, kV) for the selected
channel.
Measuring
mode
The amplitude setting of the measured signal is
made separately for each channel using the
arrow buttons.
5 V/Div.=
5.0
Channel
Coupling
Preset
measurement
Go to
Print
Multimeter
Help
202/085
A slider enables you to shift the curve vertically, separately for each channel.
Test Instruments
Preset measurement
A pullup menu appears when you press the button "Coupling".
The possible selections have an influence on the
display of the curve, e. g. reference potential
(GND), DC and AC voltage components.
Auto mode
Injector,Passat B5,ADR,92KW
Hall sender-G40,Passat B5,ADR,92KW
Lambda probe-G39,Passat B5,ADR,92KW
Test Instruments
DSO
Auto level mode
Hall sender G40,Passat B5,ADR,92KW
5 V/Div.=
50 ms/Div.
Freeze Frame
Channel A
Channel B
Trigger mode
Measuring
mode
Display
Sprung
Following pressing of the button
"Preset measurement", a list of preset curves
appears.
With the preset measurements, there will be a
"Document" button in the future for the display of
additional information (e. g. adaptation of measuring leads, recording conditions such as engine
speed or temperature).
Hilfe
Drucken
T
0
Multimeter
Preset
measurement
Go to
Help
Print
The curve selected from the list is displayed in a
different colour in the mask "DSO" by pressing
the button "Display".
202/086
Auto level mode
Hall sender G40,Passat B5,ADR,92K
Test Instruments
DSO
5 V/Div.=
The current curve (red) can then be compared
with the fixed curve.
Freeze Frame
50 ms/Div.
Channel A
Channel B
The current curve is permanently updated as
long as "Freeze Frame" has not been selected.
Trigger mode
Measuring
mode
0
Multimeter
Preset
measurement
Go to
Print
Help
202/087
28
The test parameters of the selected channel are
set to the values with which the "Preset measurement" was saved. The parameters of the selected
channel can then no longer be set freely.
By pressing the button "Freeze frame", the cyclic
repetition of the measurement can be stopped or
continued.
Cursor 1 with measuring line
Test Instruments
DSO
5 V/Div.=
Auto level mode
50 ms/Div.
Freeze Frame
Amplitude channel A
13,4 V
Time value
-100,0 ms
The buttons "Cursor 1" and "Cursor 2" are displayed in the freeze frame function. The voltage
values of the curves can then be displayed separately for each channel.
The associated voltage value of each curve can
be determined by shifting the cursor position.
Cursor 1
0
T
Cursor 2
Multimeter
Cursor
Go to
Print
The time value represents the distance from the
trigger point "T".
Help
202/081
Shifting of cursor 1
(fine adjustment)
Cursor 2 with measuring line
Test Instruments
DSO
5 V/Div.=
The difference in amplitude is displayed automatically if both "Cursor" buttons are selected.
Auto level mode
50 ms/Div.
Freeze frame
Amplitude difference A
13,1 V
The difference in amplitude results from the difference between the voltage value of the curve
at the position of cursor 1 and the voltage value
at the position of cursor 2.
Time difference
244 ms
Cursor 1
0
T
Cursor 2
Multimeter
Cursor
Go to
Print
The difference in time is the interval from cursor 1
to cursor 2.
Help
If both cursors are selected, only cursor 2 can be
shifted on the curve.
202/023
Shifting of cursor 2
(fine adjustment)
29
Measurements and analysis with the VAS 5051
Sensor analysis with the DSO
Engine speed sender G28
J 220
The engine speed sender is a speed and reference marker sender. The engine does not run
without this signal.
T80/67 T80/63 T80/56
2
3
The adjacent circuit diagram shows the electrical
connections on the engine speed sender G28 of
the 1.8 l/92 kW petrol engine.
The signal for analysis by the DSO is measured
at the following contacts:
1
DSO 1 (+)
DSO 1 (–)
G 28
→ Contact 1 (signal)
→ Contact 2 (ground)
202/038
Remove the connector from the engine speed
sender G28 and connect again using the measuring leads
•V.A.G. 1594/1
•V.A.G. 1594/2 and
•V.A.G. 1594/19
from the V.A.G. 1594A test set.
The speed signal between contacts 1 and 2 can
then be displayed as a curve on the DSO.
1 2 3
The following curve is obtained:
V.A.G. 1594/1
1 2 3
V.A.G. 1594/2
DSO measuring lead
V.A.G. 1594/19
30
202/037
Auto level mode
Test Instruments
DSO
5 V/Div.=
10 ms/Div.
Freeze Frame
Channel A
Channel B
Trigger mode
0
Measuring
mode
0.0
Channel
Coupling
Preset
measurement
Go to
Print
Multimeter
Help
202/059
The crankshaft signal wheel has 60 teeth with
two gaps of 2 teeth for synchronization.
The two gaps can be clearly seen in the above
diagram.
31
Measurements and analysis with the VAS 5051
Hall sender G40
J 220
T80/62
T80/76
1/+
2
3/-
The Hall sender signal enables the engine control unit to recognize the ignition position for
cylinder 1 with ignition systems without a distributor.
The ignition point for the other cylinders and the
commencement of injection are calculated from
this.
T80/67
The adjacent circuit diagram shows the electrical
connections on the Hall sender G40 of the
1.8 l/92 kW petrol engine.
The electric signal of the Hall sender for subsequent analysis by the DSO is measured at the
following contacts:
G 40
202/044
DSO 1 (+)
DSO 1 (−)
→
→
Contact 2 (signal)
Contact 3 (ground)
The connection to the control unit must not be
interrupted in the process, otherwise the engine
will stop.
The Hall sender signal between contacts 2 and 3
can be displayed as a curve on the DSO by intermediate connection of an adapter lead from the
V.A.G. 1594A test set which permits parallel connection of the DSO measuring lead of the VAS
5051 tester on the Hall sender.
1
2
3
The individual adapter leads are described on
page 30.
The following curve is obtained:
202/075
32
Auto level mode
Test Instruments
DSO
5 V/Div.=
50 ms/Div.
Freeze Frame
Channel A
Channel B
Trigger mode
0
Measuring
mode
0.0
Channel
Coupling
Preset
measurement
Go to
Print
Multimeter
Help
202/058
The Hall sender is OK if the
curve is uniform and periodic.
33
Measurements and analysis with the VAS 5051
Coolant temperature sender G62
The signal from the coolant temperature sender
G62 is used by the engine control unit as a correction factor for the basic injection timing
depending on the engine temperature (warm-up
period).
J 220
T80/54
T80/70
1
2
3
4
G 62
The adjacent circuit diagram shows the electrical
connections on the coolant temperature sender
G62 of the 1.8 l/92 kW petrol engine.
The electric signal for subsequent analysis by the
DSO is measured at the following contacts:
G2
DSO 1 (+)
DSO 1 (−)
202/039
→
→
Contact 1 (signal)
Contact 3 (ground)
The coolant temperature sender G62 controls the
coolant temperature gauge in the dash panel
insert.
The temperature signal between contacts 1 and 3
can be displayed as a curve by intermediate
connection of an adapter lead from the V.A.G.
1594A test set.
1
The individual adapter leads are described on
page 30.
3
The following curve is obtained:
202/074
34
Draw mode
Test Instruments
DSO
5 V/Div .=
100 s/Div.
Freeze Frame
Channel A
Channel B
Trigger mode
0
Measuring
mode
0.0
Channel
Coupling
Preset
measurement
Go to
Print
Multimeter
Help
202/060
This signal via the adapter leads is slightly falsified by interfering fields, e. g. the ignition cables.
However, the falling trend on warming-up of the
engine can be recognized.
The voltage curve shows the change in temperature of the engine or coolant from approx. 10 °C
up to 90 °C.
900
Ω
7
700
kΩ
600
5
500
4
400
3
300
2
200
1
100
0
10
20 30
40
50
60 70
80
Exact judgement of the engine temperature
sender is possible using the resistance characteristic from the corresponding workshop
manual.
The characteristic shows the corresponding
resistance value of the sender depending on
the temperature.
The sender is OK if the resistance value is
within the shaded area.
°C 100
202/089
35
Measurements and analysis with the VAS 5051
Lambda probe G39
J 220
The lambda probe is located in the exhaust pipe
upstream of the catalytic converter.
The engine control unit receives a voltage signal
from the lambda probe on the composition of the
exhaust gas.
The engine control unit controls the injectors such
that the quantity of injected fuel results in an air/
fuel ratio of approx. λ = 1.0.
T80/26 T80/25 T80/27
4
3
2
The adjacent circuit diagram shows the electrical
connections on the lambda probe G39 of the
1.8 l/92 kW petrol engine.
G39
The electric signal for subsequent analysis by the
DSO is measured at the following contacts:
1
+/87F
202/042
DSO 1 (+)
DSO 1 (−)
→
→
Contact 4 (signal)
Contact 3 (ground)
The lambda probe adapter VAS 5103 is used to
connect the tester measuring leads to the lambda
probe connector.
The adapter lead is designed for two different
versions of lambda probe connectors.
Lambda probe adapter VAS 5103
The unused connector must be
disconnected.
1 2
The lambda probe heating signal between contacts 1 and 2 and the lambda probe signal
between contacts 3 and 4 can be displayed as a
curve by intermediate connection of the adapter
lead which permits parallel connection of the
DSO measuring lead of the VAS 5051 tester to
the connector for the lambda probe.
3 4
4
3
2
1
4
3
2
The following curve is approximately obtained
for the lambda probe signal at idling speed:
1
202/073
36
Draw mode
Test Instruments
DSO
0,2 V/Div.=
1 s/Div.
Freeze Frame
Channel A
Channel B
Trigger mode
Measure mode
0
Channel
Coupling
Preset
measurement
Go to
Print
-0.40
Multimeter
Help
202/061
The visible deviations (peaks) are not faults in the
lambda probe signal, they are interferences from
the ignition system. They are "received" via the
adapter leads and the DSO lead.
The voltage signal for a rich mixture with little
residual oxygen is approx. 0.7 ... 1.1 V.
The voltage signal for a lean mixture with a lot of
residual oxygen is approx. 0.1 ... 0.3 V.
The following faults may be present if the change
in voltage does not take place or is sluggish:
-
Holes in probe head blocked
Excessive thermal stress
Probe too cold, probe heating not functioning
Lambda control switched off, engine control
unit has recognized fault in injection
system -> interrogate fault memory.
The transition from rich to lean and vice versa is
accompanied by a voltage jump from 0.7 ... 1.1 V
to 0.1 ... 0.3 V or vice versa.
The control continuously oscillates between the
statuses "slightly too lean" and "slightly too rich".
37
Measurements and analysis with the VAS 5051
Knock sensor G61
J 220
T80/67
The knock sensor records the vibrations of the
engine during knocking combustion, and passes
a signal on to the engine control unit.
The engine control unit then sets the ignition
point to "Retard". This allows the engine to be
driven with different fuel qualities.
T80/68
The function diagram for the knock sensor is
shown on the left.
2
1
3
The electric signal for subsequent analysis by the
DSO is measured at the following contacts:
DSO 1 (+)
DSO 1 (−)
G 61
→
→
Contact 1 (signal)
Contact 2 (ground)
202/043
The function of the knock sensor can be checked
from the curve by intermediate connection of an
adapter lead from the V.A.G. 1594A test set.
The DSO measuring lead is connected parallel to
the contacts 1 and 2 of the knock sensor.
The following curve is obtained:
1 2 3
1 2 3
V.A.G. 1594/1
V.A.G. 1594/2
DSO measuring lead
V.A.G. 1594/19
38
202/072
Auto level mode
Test Instruments
DSO
0,5 V/Div.=
10 ms/Div.
Freeze Frame
Channel A
Channel B
Trigger mode
0
Measuring
mode
0.0
Channel
Coupling
Preset
measurement
Go to
Print
Multimeter
Help
202/062
The curve shown above can be obtained
e. g. by gently knocking on the mounting screw of
the knock sensor.
39
Measurements and analysis with the VAS 5051
Actuator analysis with the DSO
Injectors N30 ... N33
The injectors are located in the manifold
upstream of the associated inlet valve.
J 220
T80/73 T80/80 T80/58 T80/65
+/87F
234
2
2
2
2
The adjacent circuit diagram shows the electrical
connections of the individual injectors of the 1.8 l/
92 kW petrol engine.
234
15A
234a
The injectors are controlled by the engine control
unit by means of electric pulses.
The injection quantity is controlled by the engine
control unit by means of the injection period
since the cross-section of the opening and the
difference in pressure are constant.
1
1
1
1
N30
N31
N32
N33
The electric signal for subsequent analysis of an
individual injector by the DSO is measured at the
following contacts:
10e/8
202/040
DSO 1 (+)
DSO 1 (−)
→
→
Contact 2 (signal)
Contact 1 (positive)
The injection signal can be displayed as a curve
by intermediate connection of an adapter lead
from the V.A.G. 1594A test set into the wire to an
injector with the DSO measuring lead of the VAS
5051 tester connected.
The individual adapter leads are described on
page 30.
Faults can be detected compared to a defined
curve.
The following curve is obtained:
202/076
DSO measuring lead
40
Auto level mode
Test Instruments
DSO
20 V/Div.=
5 ms/Div.
Freeze frame
Channel A
Channel B
Trigger mode
0
Measure mode
0.0
Channel
Coupling
Preset
measurement
Go to
Print
Multimeter
Help
202/063
The curve shows the voltage response on the
injector. The voltage peak results from discharging of the magnetic field.
The injection period is proportional to the injection quantity.
41
Measurements and analysis with the VAS 5051
Activated charcoal filter solenoid valve N80
J 220
The activated charcoal filter solenoid valve is a
valve in the tank venting system.
The solenoid valve closes the tank venting system
downstream of the activated charcoal filter and
is only opened electrically by the engine control
unit.
The solenoid valve is activated periodically by
the engine control unit according to evaluation of
the lambda probe, the throttle valve sender and
the coolant temperature sender.
T80/15
2
The adjacent circuit diagram shows the electrical
connections of the activated charcoal filter solenoid valve on the 1.8 l/92 kW petrol engine.
1
N80
The electric signal for subsequent analysis by the
DSO is measured at the following contacts:
DSO 1 (+)
DSO 1 (−)
+/87F
→
→
Contact 2 (signal)
Contact 1 (positive)
202/051
The solenoid valve control signal can be displayed as a curve by intermediate connection of
an adapter lead from the V.A.G. 1594A test set
into the lead to the activated charcoal filter solenoid valve with the DSO measuring lead of the
VAS 5051 tester connected.
2
1
The individual adapter leads are described on
page 30.
Faults can be detected compared to a defined,
preset measurement.
The following curve is obtained:
202/077
42
Auto level mode
Test Instruments
DSO
20 V/Div.=
10 ms/Div.
Freeze Frame
Channel A
Channel B
Trigger mode
0
Measuring
mode
0.0
Channel
Coupling
Preset
measurement
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Multimeter
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202/066
The opening duration and the switching frequency of the activated charcoal filter solenoid
valve can be recognized from the displayed
curve.
43
Measurements and analysis with the VAS 5051
Your attention must finally be drawn to the following points for evaluation of displayed curves
which deviate greatly from one of the preset
curves:
-
-
Only curves recorded under the same conditions or prerequisites can be compared with
one another
Fluorescent lamps may produce interfering
signals
The ignition transformer and leads emit interfering signals which may be superimposed
on the actual curve or falsify it.
If the DSO test probes are not
connected correctly, it may occur that
interfering signals from the ignition
system are displayed, and not the
expected sender or actuator signal.
The curves shown here are examples which cannot be used as correct curves for fault finding.
Auto level mode
Test Instruments
DSO
0,2 V/Div.=
50 ms/Div.
Freeze Frame
Channel A
Channel B
Trigger mode
Measuring
mode
0
-0,16
Channel
Coupling
Preset
measurement
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Multimeter
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202/078
The displayed curve shows the typical waveshape of interference from illumination by
fluorescent lamps.
The interfering curve is superimposed on the
measured curve, and changes the overall
curve.
44
Auto level mode
Test Instruments
DSO
0,2 V/Div.=
50 ms/Div.
Freeze Frame
Channel A
Channel B
Trigger mode
Measuring
mode
0
-0,16
Channel
Coupling
Preset
measurement
Go to
Print
Multimeter
Help
202/079
The displayed curve shows the typical waveshape of interference from the use of a portable
lamp on the vehicle in the immediate vicinity of
the measuring leads.
Auto level mode
Test Instruments
DSO
0,2 V/Div.=
0,5 ms/Div.
Freeze Frame
Channel A
Channel B
Trigger mode
0
Measuring
mode
0.0
Channel
Coupling
Preset
measurement
Go to
Print
Multimeter
Help
202/080
The displayed curve shows the typical waveshape of interference from incorrectly connected
probes of the DSO measuring lead.
45
Notes
46
47
202
Service.
For internal use only © VOLKSWAGEN AG, Wolfsburg
All rights reserved. Technical data subject to change without notice.
740.2810.21.20 Corresponds to technical state 11/97
❀ This paper was produced from
chlorine-free chemical pulp
48